Alternating-current plant combined with storage battery.



No. 847,974. TATENTED MAR. 19, 1907. L. SGHRUDER & A. MULLER. ALTERNATING CURRENT PLANT COMBINED WITH STORAGE BATTERY.

APPLIGATION FILED JULY 14 1905.

4 SHEETS-SHEET l 5 M W W Wmummm I a No 847,974 PATENTED MAR. 19, 19074 L. SOHRUDER & A. MULLER.

ALTBRNATING CURRENT PLANT COMBINED WITH STORAGE BATTERY. APPLICATION FILED JULY14, 1905.

4 SHEETS-SHEET 2 y N i x !IHIIIIIIIIHIIHIIIIIIHIIIIIIIIII No. 847,974. PATENTED MAR. 19, 1907. L. SGHRUDER & A. MULLER.

ALTERNATING CURRENT PLANT COMBINED WITH STORAGE BATTERY. APPLICATION FILED JULY 14. 1905.

' 4 SHEETS-SHEET sv @HWH'IWI l l l l l i l l l HI I HW ymofiwm vww o PATENTED MAR. 19, 1907 L. SCHRUDER & A. MULLER.

ALTERNATING CURRENT PLANT COMBINED WITH STORAGE BATTERY.

j/QRW APPLICATION FILED JULYIA,1905.

SHEETSSHEET 4" unIMMMIHIIIHIHHIW'f .sTArns .arnrar r'rcn.

I A LTERNATlNG-CURRENT PLANT COMBINED WITH STURAGE BATTERY.

Specification. of Letters Patent.

Patented March ie, 1907.

Griginal application filed October 7, 1904, Serial No. 227,527. Divided and this application filed-Tilly 14, 1905. Serial No. 269,632.

To all whom it may concern;

Be it known that we, LUDWIG .SoHRonER, a citizen of the free and Hanseati'c' town Hamburg, Empire of Germany, and a resident of 31 Luisenstrasse, Berlin, Germany, and ADOLPH MilLLER, a subject of the Prince of Waldeck, Dominion-of the Prince Friedrich von Waldeck, Empire of Germany, and a resident of 31 Luisenstrasse, Berlin, Germany, have inventedcertain new and useful Improvements in Alternating-Current Plants Combined with Storage Batteries, of which the following is a specification.

Our invention relates to alternating-current plants combined with storage batteries, and has the purpose toregulate the charging and .dischargin of the storage battery in such a mannert at if the current used in the plant varies the prime mover actuating the main enerator continues working with constant oa'd.

This application is for a division of our.

pending application, Serial No. 227,52 7,'filed October 7, 1904.

well known, electric plants the cur rents of which are subjected to great fluctuations are vcombined'with a storagebattery being charged by the excess of current not used in the plant and discharging current into the plant if there is more current wanted than generated by the main generator; ln alternating-current plants a motor-generator is to be used, as the storage battery can only be charged by a direct or continuous current,

' and producing alternating the alternating current portion of this motor-gytenerator being connected with the wires eplant and the direct-current portion being connected with the storage battery.

.' If a small current is used in the plant, the

excess of current roduced by the main enerator'will drive t e motor-generator and the current producedby the'direct-current portion will charge the battery. It, on the contrary,-the plantuses more current than the main generator can 1produce, then the altere natingyportion oft motor gen mt will ,be; driven b the .direct current portion, the "battery disc arging current into this portion current assisting the current producedby t of. main generator.

-In this known system no special means were provided .to regulate the charging and ,dis-

charging current. automatically, this reglilishunt of g e direct-current portion hereafter.

the transformer. The regulating of the charging and discharging current was automatical only in the case when by a strong declivity of the characteristic of the main generator the fluctuations of intensity cause the ten sion of the alternating current to rise or to fall considerably.

Now our invention consists in regulating automatically the charging and discharging current of the battery, even if there are no variations in thetension of the alternatingcurrent plant, in such a manner that the prime mover actuating the main generator is working always with constant load.

We do not limit ourselves to any particular kind of alternating current, but prefer ably use the apparatus in connection with the so-oalled polyphase system, as shown drawings to a.

in the accompan part of this specification, in w 'ch similar characters of reference indicatecorrespond,

i parts in all-the figures.

' igures land 2 show difierent forms of the invention to be described more specially F1 3. is a diagrammatic perspective .view rowing an arrangement somevs Y what similar'to that in Fig. 1, butshowing instead the rotary converter D and an electrolytic rectifier which transmits, merely currents of negative sign, so that the field of the booster is excited by pulsationsof-the current from the rectifier; and Fig; 1a is a -dia rammatic perspective view somewhat similar to Fig. 3, but showingfsome additional connections not present in Fig. 3.

In Fig. 1 the main alternating-current gengine, turbine, or another prime mover Mjthe main alternating-current motor atLE, representing a whole plant, astorage battery at F, connected with thedynamo C, driven by the prime mover M. A transformer G is connected with the alternating-current portion of a rotary converter D, the direct portion of the latter being connected by the wires .9 10 with a winding i u on the field of the dynamo erator is shown atA, driven by a steam-env C. Another win ing' h'upon the field ofthe 1 direct-current dynamo O opposes the, winding 11 and is connected with the storage batteryF by the wiresll and-12,2 c,

. The action-of the system is? as follows: The main gene 'atorAbein energized and the current used in t lie plant being very small, the current flowing through the secondary windin of G, being also small, will be con- .verted y the rotary converter D into'a small direct current flowing through the winding '11.

ates current, which flows to the storage battery. The high electromotive force of this current necessary for charging the battery is produced by the field highly excited by the winding h proportional to the electromotive force of the battery and weakened only in a small degree by the small current flowing through the opposite winding i. The battery F is therefore charged with a large current and a high electromotive force if the amount of current used in E is small. If an excess of current is wanted in E, the direct current in the winding 01 is large, thereby weakening strongly the magnetic field and the electromotive force of the direct-current dynamo C to such a degree that the electromotive force of the battery F is greater than that of the dynamo C. Therefore the battery F is discharged into the dynamo O, energizing it as a motor and driving it, so that the prime mover is assisted by the dynamo C acting now as motor. Therefore if the amountof current used in the plant E is small the direct-current dynamo G acts as a generator, the electromotive force of which is augmented in the manner explained with reference to Fig. 1. If an excess of current is wanted in E, the electromotive force of C is diminished in the manner explained before, and the battery F is discharged into C, causing it to act as a motor and to help the motor M in driving the main generator A. In this arrangement the main 'eneratori iworks at variable load, as it must furnish the Whole amount of current as large or as small as may be wanted in the plant,

and therefore the tension of the current will var Ih the form of our invention'shown in Fig. 3 the direct-current d amo L as well as the booster are coupled with the prime mover M, this system acting in the same manner as the form Fig. 1, the maingenerator A working at variable load, as it furnishes the whole current used in E. On the contrary, the prime mover M is always workin with constant load, as it is assisted by the ynamo L acting as motor if more current is used in E as produced by the main generator A, while the dynamo L produces current charging the battery F if less current is used in E.

In Fig. 2 the connections are the same as in Fig. 1, except that the dynamo L is connected tothe prime mover instead of to the m0- tor-generator.

In Fig. 3 the arrangementis very much like that shown in Fig. 1. The chief difierence is in the fact that in this figure an electrolytic rectifier 2, provided with terminals a b, is substituted for the rotary converter D in Fig. 1. The pur ose of the electrolytic rectifier is to insure t at a direct through in termittent winding i. v x

In Fig. 4 there are several electrolytic rectifiers Z, Z Z and Z, each being provided with terminals (1 b, so connected as to split the current induced by the transformer g, a part of this current returning directly to the transformensecondary and a part being used to energize the winding i.

/ In all forms of the invention the rotary converter D may be of any suitable form and even be substituted by an electrolytic rectifier. Fig. 4.- shows such electrolytic rectifier j in combination with the form of the invention described with referenceto Fig. 1. The secondary portion of the transformer G is connected hy wire 7 to one or more aluminium plates a of an electrolytic rectifier Z, the plates 6 of which, consisting of another met al, are connected bywire 8 to the winding i of the direct-current dynamo C, which is coupled with the prime mover M. The other end of the Winding 'i is connected directly with the secondary portion of the transformer G by wire 9. As is very well known, the aluminium electrodes a of the electrolytic rectifier transmit only the negative parts of the alternating current, preventing the flow.- ing of the other parts of the current. Fig. 5 shows another known form of this electro lytic rectifier in combination with our sys' In this form there are four cells Z Z tem. Z Z the plates a and b of the cells Z and Z current will be sent through the being connected by Wire 8 to the secondaryportion of the transformer G and the plates a and b of the cells Z and Z being also connected by wire 7 to the transformer G. The winding 1' of the direct-current dynamo C is connected by wire 9 to the plates a of cell Z and Z and by wire -1O to the plates 1) of cell "Z and Z By this means a pulsating direct current will flow through the winding'i of the direct-current dynamo C. Such electrolytic rectifier may be used in all other forms of the invention instead of the rotary converter D.

The booster K instead of being driven by the prime mover M may also be driven by any other motor or electric machine.

Having thus described our invention, we claim as new and desire to secure by Letters Patent- 1. In an alternating-current plant the combination of a direct-current machine coupled with the rime mover a storage battery connected wit the machine, converting device connected with the wires of the plant and producing a direct current in a separate winding on the field of the direct current ma- .chine charging the storage battery orbeing driven by the current of this battery and regulating thereby automatically the charging and discharging of the battery in such a manner that the prime mover actuating the main generator works with constant load.

' 2. The combination of an alternating-cur- I rent generator, an alternating-current motor,

. electrical connections from said alternating I current generator to said alternating-current direct-current generatoras' a unit, astorage Iro battery, connections from said direct-current generator thereto, means connecting said last-mentioned connections with one of said windings of said direct-current generator and electrical mechanism controllable by currents from said alternating-current gene'rator for energizing the other of said Windings of said'alternating current generator.

3. In an alternating-current plant the combination of a direct-current machine coupled with the prime mover, a storage battery connected with this machine a booster driven by suitable means and converting devices connected with the Wires of the plant and producing a direct current in a separate.

winding on the field of the booster regulating thereby automatically the charging and discharging of the battery in such a manner that the prime mover actuating the main generator Works with constant load.

4. The combination of a direct-current generator provided with two field-windings in op osition to each other, a storage battery supp ied by said directcurrent generator and connected with one of said field-windings for energizing the latter, a separate generator connected mechanically with said direct-current generator, and electric mechanism centrollable by said separate generator and connected with the other of said field-windings.

In Witness whereof we have hereunto signed our names in the presence of two subscribing witnesses.

LUDWIG SCHRODER. ADOLPH MULLER. Witnesses:

HENRY HAsrnn, WoLnnn'Aa HAUPT. 

